BS ISO 516:2019

What is  ISO 516 about?    ISO 516 provides a uniform basis for determining the exposure times for all types of shutters used in still cameras and contains suitable definitions of the terms used. It specifies the exposure-time markings for all types of shutters and their tolerances. Test methods are described for routine manufacturing testing and quality control.

Who is  ISO 516 for?   ISO 516 for   camera shutters is applicable to: 

photographers end Consumers camera manufacturers 

Why should you use  ISO 516 ?   ISO 516 defines  the characteristics of all types of mechanical shutters, which are mounted in still cameras and affect the control of exposure, motion-stopping ability, and synchronization with a photoflash light source. The tolerances specified are the target values for the shutter performance that can be expected to give good results. These test methods require access to the focal plane of the camera and can therefore not be applied to assembled digital still cameras. ISO 516 also provides guidelines on testing for the effect of light on photos of digital cameras which can improve the quality of photos. What’s changed since the last update? 
ISO 516:2019 supersedes ISO 516:1999 , which is withdrawn. ISO 516:2019 cancels and replaces the third edition ( ISO 516:1999 ) which has been technically revised. The title and scope have been updated to reflect that the document is app...